According to The Code on Unions and Collective Employment Contract Law No 6356, three types of collective employment contract can be made as business, enterprise and group collective employment contracts. Among them, the enterprise collective employment contracts bring along some problems due to the use of the phrase "enterprise". As a matter of fact, in the second paragraph of Article 34 of the Law No. 6356, it is regulated as a necessity to conclude a collective employment contract at the enterprise level if there is more than one workplace in the same business line. However, the concept of job in the legal definition does not express a job element as we know it, in fact, it is used to cover all these workplaces in case the same employer has more than one workplace in the same business line. In this framework, in our study, both the determination of the nature of the enterprise, where the obligation to make a collective employment contract is on the agenda, and the problems created by the relevant contract type in practice will be examined.